1. Field of the Invention
The invention relates to a rolling bearing apparatus and a detection method for abnormality in a rolling bearing, and in particular, to a rolling bearing apparatus equipped with a detector configured to detect abnormality and a detection method for abnormality in the rolling bearing apparatus.
2. Description of the Related Art
Detection units are available which detect abnormality in a rolling bearing based on a rotation speed and vibration. For example, in a rolling bearing apparatus described in Japanese Patent Application Publication No. 2003-308588 (JP 2003-308588 A), a speed detection unit and a vibration sensor are mounted. Specifically, in JP 2003-308588 A, the vibration sensor is attached to a housing of the bearing apparatus. The speed detection unit includes a coil and a magnet. The coil is wound all around the bearing, and the magnet is fixed to a rotating member.
The rolling bearing apparatus detecting the rotation speed and vibration needs both sensors, that is, the detection unit (sensor) configured to detect the rotation speed and the vibration sensor as described in JP 2003-308588 A. Thus, the rolling bearing apparatus disadvantageously has a large number of components and a complicated configuration. The rolling bearing apparatus needs a space where the coil is wound and a space where the vibration sensor is mounted. Thus, the rolling bearing apparatus also disadvantageously has an increased size.